hello, i also wanted to share the way i reference the level blueprint.
The main idea is making the level blueprint implement an interface then using variables of that interface in your actors.
i made a video showing it : https://www.youtube.com/watch?v=hlre9E3wA3A
I used this method because i got to work in someone else project, with all the code placed in the level blueprint, and it was so much code i just had to find a way to get a direct reference to all the functions and custom methods living in the levelblueprint.